Here's more trivia for you, then:
The scene in your response was from the last episode aired of the original series.
The episode, 'Turnabout Intruder' featured Kirk experiencing a body swap with a female - Doctor Janice Lester. The frame you supplied is a tense point when Dr. Lester is freaking out in Kirk's body.
If I remember correctly, they used the transporter to restore each personality to the correct body. And it was one of the worst episodes ever. It's no surprise the show was canceled. But long before then, the show was already in a nosedive, never to recover. NBC just wasn't interested in Star Trek.
The show had been moved by studio execs to a time when no one would see it, and funding was almost non-existent. Due to this lack of funds, many of the third season episodes were poorly written and forced to occur on the ship, further reducing the odds of an interesting plot.
It took the box office success of Star Wars to wake the executives up to the future earnings potential of the franchise. For this reason, Star Trek: The Motion Picture was made, igniting interest from new and existing fans for the first voyage of the refitted and modernized Enterprise.
And for even MORE ratings, they killed Spock in the sequel.
